This invention relates generally to cutting blades, sharper cutting blades and particularly to sharper arrowhead or broadhead cutting blades.
Arrows have long been used for war, hunting and competitive sports. A conventional arrow has a shaft, a nock at one end that receives the bow string, an arrowhead or point that attaches to the opposite end, and fletchings. The fletchings are glued to the shaft near the nock end, and help to stabilize the arrow in flight by causing it to rotate. Arrowheads generally have a pointed forward end, and an opposite threaded shaft end that attaches the arrowhead to the arrow shaft. Arrowheads are also attached to the forward end of arrow shafts by glueing and other methods.
Arrowheads come in a variety of different sizes and configurations depending on their intended use. For example, there are specifically designed arrowheads for competitive target shooting, shooting fish, hunting birds or small game animals, and for hunting big game animals.
Arrowheads used for hunting generally kill the game animal by cutting vital organs such as the lungs and vascular vessels such as arteries, which causes rapid hemorrhaging and/or suffocation. Quick and humane kills are dependent on accurate shot placement, and upon the amount or volume of the animal tissue that is cut. Hunting arrowheads that cut more tissue are more lethal, and therefore are better. The volume of tissue that is cut is determined by the cutting diameter of the arrowhead, the number of blades it contains, and by the distance the arrowhead penetrates into the animal. The sharper the cutting edge of the arrowhead blade(s) (all other factors being equal) the greater the depth of penetration will be.
A cutting edge of a cutting blade, such as those used with hunting arrowheads is formed on a section of blade-stock material by grinding or otherwise fabricating an acute angle along an edge of the blade stock material. This process usually forms a bevel or bevels on both opposing side faces of the blade-stock material. Generally, the sharpness of an arrowhead cutting blade (all other factors being equal) is determined by the angle between opposing bevels on either side of the cutting edge of the blade; the narrower the angle between the opposing bevels the sharper the cutting edge is. A common method for manufacturing arrowhead blades is the process of strip grinding, wherein generally a pair of primary grind bevels is first ground on opposing sides of the metal strip (blade stock material) so that an acute angle (the cutting edge) is created along an edge of strip, whereupon a pair of hone grind bevels is generally ground on the primary grind bevels so as to yet further define the cutting edge with another acute angle, and lastly the cutting edge is generally stroppedxe2x80x94wherein microscopic burrs are removed from the cutting edge.
A common type of arrowhead used in hunting is the fixed-blade arrowhead, which has a pointed tip end used for penetrating, and generally triangular shaped fixed-blades or non-pivotal blades that each have a razor sharp edge for cutting. Conventional fixed-blade arrowheads blades are held in a fixed position on the arrowhead, and most such blades are replaceable. The replaceable blades attach to the arrowhead body in longitudinal grooves called blade slots. The tip of the arrowhead may be separably attachable to the arrowhead body or may be integral with it. Arrowheads for hunting are generally known as broadheads. Some types of fixed-blade arrowheads have a cutting blade extending to the forward terminus of the arrowhead, such as flathead arrowheads and traditional cut-on-contact arrowheads.
Another popular type of arrowhead for hunting is the blade-opening arrowhead. Blade-opening arrowheads are generally known as mechanical broadheads. Blade-opening arrowheads, like conventional fixed-blade arrowheads generally have an elongate arrowhead body, a tip end, and a threaded opposite end. The blades of blade-opening arrowheads have an attachment end which attaches the blades to the arrowhead body by a shaft or a pivot pin, so that the blades can pivot, rotate or expand between a closed position and an open position. Blade-opening arrowhead blades are generally an elongate substantially rectangular shape and also have a free non-attached end situated opposite the attachment end. The blades of blade-opening arrowheads are also received in blade slots, which are machined or formed into the arrowhead body. The expandable or pivotal blades of blade-opening arrowheads are held in the closed position while in-flight, until the arrowhead penetrates a game animal or target, by various different methods including: conventional rubber O-rings, rubber bands, tight fitting plastic sleeves, tape, heat-shrinkable sleeves, and other wrap materials as well as by magnetism, various spring systems, friction detents and other frictional mechanisms. When the expanding blades of blade-opening arrowheads are retracted or folded into the closed position, a substantial majority of each blade is generally housed within its corresponding blade slot. This feature gives blade-opening arrowheads the ability to attain significantly increased aerodynamic performance over fixed-blade arrowheads, due to the significantly decreased exposure the retracted blades have with the air when the arrow is rotating while in flight. Such increased aerodynamic performance results in the desirable features of: faster shooting arrows, flatter arrow trajectories, increased penetration energy and enhanced repeatability of accuracy, while also providing a wide diameter cut in the game animal when the razor sharp blades open at impact with the animal.
Blade-opening arrowheads come in a variety of different types and styles. The most common type of blade-opening arrowhead has blades that are pivotally connected to the arrowhead body at a location near the rear end of the arrowhead body. This makes it so that when the blades are folded into the retracted position a leading blade end of each blade positioned near the tip of the arrowhead protrudes outward from the arrowhead body. The leading blade ends of such blade-opening arrowheads rotate or expand away from the arrowhead body in a rearward direction when penetrating an animal. Particularly, the leading blade ends catch on the animal""s surface and serve to lever or rotate the blades into the fully open position, thus exposing the sharp cutting edges of the blades to a fully open cutting diameter position and cutting the animal. Another type of blade-opening arrowhead has pivotal blades that rotate or expand in a forward direction to the fully open position when penetrating an animal. The blades of these forward blade rotating/expanding blade-opening arrowheads are rotated or expanded toward the open position by a variety of different mechanisms, but all also define a fully open cutting diameter when in the open position.
Yet another type of arrowhead used for hunting has pivotal blades that are exposed at a full cutting diameter position while the arrowhead is in-flight. Such arrowheads also generally achieve better aerodynamic performance than fixed-blade arrowheads because by design each pivotal blade only attaches to a corresponding arrowhead body at a single location so that with their substantially elongate shaped blades such arrowheads have significantly decreased blade surface area exposure with the air while in-flight.
Arrowheads having expanding blades, or cutting blades attached to an arrowhead body by a pin or a shaft, like most blade-opening arrowheads, generally need to have thicker blades for strength purposes than that of fixed-blade arrowhead blades. This is such because expanding or pivotal blades are generally attached to corresponding arrowhead bodies at only one location (the pin) and therefore can more readily be damaged by the high impact forces encountered at target penetration from impacting bone and/or other similar materials than can the blades of fixed-blades arrowheads which are contrastingly attached to corresponding arrowhead bodies in a manner so as to contact the arrowhead body along a substantial majority of their length which therefore generally provides a greater support structure and sufficient strength for the thinner blade(s).
It is desirable for an arrowhead to penetrate as deep in the game animal as possible so as to maximize the volume of animal tissue that is cut, as well as to create both an entry hole and an exit hole in the animal for blood to drain therefrom so as to leave a more followable or noticeable blood trail.
It is desirable for an arrowhead blade or broadhead blade to be as sharp as possible so as to better cut game animals and therefore provide a more lethal broadhead.
The sharpness, or narrowness of the angle between opposing bevels on either side of the cutting edge of a cutting blade, such as a broadhead cutting blade, is generally determined by the thickness of the blade stock material the repsective cutting blade is made from. Generally, thinner blade stock material will produce a narrower angle between opposing bevels than will thicker blade-stock material, and thus since the angle is narrower the cutting edge is sharper (all other factors being equal).
Therefore, since mechanical broadhead blades are generally thicker than fixed-blade broadhead blades for strength purposes, mechanical broadhead blades generally do not have as sharp of cutting edges (as narrow of angle between opposing grind bevels) as do fixed-blade broadhead blades. Also, thicker blades require more time to grind when sharpening, and thus are more expensive to produce.
It is apparent that there is a need for a sharper cutting blade. It is apparent that there is a need for an improved cutting blade for broadheads. It is apparent that there is a need for a thicker cutting blade which has both the increased structural strength and rigidity of a thicker blade, as well as having the sharper cutting edge (narrower angle between bevels) as does a thinner cutting blade.
It is also apparent that there is a need to more cost effectively manufacture cutting blades by reducing the time to grind/sharpen cutting edge(s) thereon, wherein the amount of time to grind/sharpen a cutting edge on a thicker cutting blade is reduced to the amount of time required to grind/sharpen a cutting edge on a thinner cutting blade.
It is an object of the present invention to provide a sharper cutting blade.
It is an object of the present invention to more cost effectively manufacture cutting blades by reducing the time to grind/sharpen cutting edge(s) thereon, wherein the amount of time to grind/sharpen a cutting edge on a thicker cutting blade is reduced to the amount of time required to grind/sharpen a cutting edge on a thinner cutting blade.
It is an object of the present invention to provide a sharper cutting blade having a cutting edge section that is not collinear with another cutting edge section of the cutting blade.
It is an object of the present invention to provide a sharper cutting blade having a cutting edge with at least a portion thereof that is substantially serrated.
It is an object of the present invention to provide a cutting blade having a cutting edge with an angle between opposing hone bevels that is substantially the angle normally attainable between hone bevels on cutting blades having thinner cross-sectional thicknesses.
It is an object of the present invention to provide a cutting blade having a cutting edge with an angle between opposing primary grind bevels that is substantially the angle normally attainable between primary grind bevels on cutting blades having thinner cross-sectional thicknesses.
It is an object of the present invention to provide a cutting blade having a cutting edge with an angle between opposing grind bevels that is substantially the angle normally attainable between grind bevels on cutting blades having thinner cross-sectional thicknesses.
It is an object of the present invention to provide a sharper razor blade.
It is an object of the present invention to provide a sharper shaving razor blade.
It is an object of the present invention to provide a sharper shaving razor blade that has the cutting edge of a thinner shaving blade and the rigidity of a thicker shaving blade.
It is an object of the present invention to provide a sharper utility blade.
It is an object of the present invention to provide a sharper surgical scalpel blade.
It is an object of the present invention to provide (a) sharper device(s) for cutting, slitting, trimming, chopping and dicing.
It is an object of the present invention to provide a sharper arrowhead cutting blade.
It is an object of the present invention to provide a sharper fixed-blade arrowhead cutting blade.
It is an object of the present invention to provide a sharper fixed-blade arrowhead cutting blade that is removably attachable with an accompanying arrowhead body.
It is an object of the present invention to provide a sharper fixed-blade arrowhead cutting blade that is non-removably attachable with an accompanying arrowhead body.
It is an object of the present invention to provide a sharper fixed-blade arrowhead cutting blade that is integral with an accompanying arrowhead body.
It is an object of the present invention to provide a sharper blade-opening arrowhead cutting blade.
It is an object of the present invention to provide a sharper blade-opening arrowhead cutting blade that is removably attachable with an accompanying arrowhead body.
It is an object of the present invention to provide a sharper cutting blade that attaches to a blade-opening arrowhead.
It is an object of the present invention to provide a sharper cutting blade that removably attaches to a blade-opening arrowhead body.
It is an object of the present invention to provide a sharper cutting blade that non-removably attaches to a blade-opening arrowhead body
It is an object of the present invention to provide a sharper cutting blade that is integral with a blade-opening arrowhead body.
It is an object of the present invention to neck down an edge of blade stock material, from which a thicker cutting blade would be fabricated from before a cutting edge is sharpened, to the thickness of a narrower blade, and then grinding or sharpening the thinner necked down edge section so as to provide a blade having the structural strength and/or rigidity of a thicker blade with a sharper or narrower angled cutting edge than it would of normally had.
It is an object of the present invention to neck down an edge of blade stock material, from which a thicker cutting blade would be fabricated from before a cutting edge is sharpened, to the thickness of a narrower blade, and then grinding or sharpening the thinner necked down edge so as to provide a blade having the structural strength and/or rigidity of a thicker blade with a sharper or narrower angled cutting edge that the narrower blade would normally have.
It is an object of the present invention to neck down an edge of blade stock material, from which a thicker cutting blade would be fabricated from before the cutting edge is sharpened, to the thickness of a narrower blade, and then grinding or sharpening the thinner necked down edge section so as to provide a blade having the structural strength and/or rigidity of a thicker blade with a sharper or narrower angled cutting edge than it would of normally had.
It is an object of the present invention to neck down an edge of blade stock material, from which a thicker cutting blade would be fabricated from before the cutting edge is sharpened, to the thickness of a narrower blade, and then grinding or sharpening the thinner necked down edge so as to provide a blade having the structural strength and/or rigidity of a thicker blade with a sharper or narrower angled cutting edge that the narrower blade would normally have.
It is an object of the present invention to provide a cutting blade fabricated from blade stock material having a plurality of different cross-sectional thicknesses before cutting edge sharpening.
It is an object of the present invention to provide a cutting blade having a side face and a cutting edge, where an inside corner is disposed between the cutting edge and the side face.
It is an object of the present invention to provide a cutting blade having a side face and a cutting edge, where an inclined bevel and an inside corner are disposed between the cutting edge and the side face.
It is an object of the present invention to provide a cutting blade having a side face and a cutting edge, where a plurality of different inclined bevels and an inside corner are disposed between the cutting edge and the side face.
It is an object of the present invention to provide a cutting blade having a side face and a cutting edge, where a plurality of different inclined bevels and an inside corner are disposed between the cutting edge and the side face on one side of the cutting edge, and at least one other bevel is disposed on another side of the cutting edge.
It is an object of the present invention to provide a cutting blade having a pair of opposing side faces on either side of a cutting edge, where an inside corner is disposed between the cutting edge and each side face.
It is an object of the present invention to provide a cutting blade having a pair of opposing side faces on either side of a cutting edge, where an inclined bevel and an inside corner are disposed between the cutting edge and each side face.
It is an object of the present invention to provide a cutting blade having a pair of opposing side faces on either side of a cutting edge, where a plurality of different inclined bevels and an inside corner are disposed between the cutting edge and each side face.
It is an object of the present invention to provide a process for manufacturing a cutting blade wherein blade stock material is necked down, along the edge of the blade stock material a cutting edge will be sharpened on, to a narrower thickness, and then at a later time grinding or sharpening a cutting edge on the thinner necked-down edge section.
It is an object of the present invention to provide a process for manufacturing a cutting blade wherein blade stock material is necked down, along the edge of the blade stock material a cutting edge will be sharpened on, before the blade stock material is in the annealed condition, to a narrower thickness, and then at a later time grinding or sharpening a cutting edge on the thinner necked-down edge section.
It is an object of the present invention to provide a process for manufacturing a cutting blade wherein blade stock material is necked down, along the edge of blade stock material a cutting edge will be sharpened on, when the blade stock material is in the annealed condition, to a narrower thickness, and then at a later time grinding or sharpening a cutting edge on the thinner necked-down edge section.
It is an object of the present invention to provide a process for manufacturing a cutting blade wherein blade stock material is necked down, along the edge of blade stock material a cutting edge will be sharpened on, to a narrower thickness, then hardening the blade stock material, and then grinding or sharpening a cutting edge on the thinner necked-down edge section.
It is an object of the present invention to provide a strip grinding process for manufacturing a cutting blade wherein blade stock strip material is necked down, along the edge of the strip a cutting edge will be sharpened on, to a narrower thickness, and then at a later time grinding or sharpening a cutting edge on the thinner necked-down edge section.
It is an object of the present invention to provide a strip grinding process for manufacturing a cutting blade wherein blade stock strip material is necked down, along the edges of the strip, cutting edges will be sharpened on, to a narrower thickness, and then at a later time grinding or sharpening cutting edges on the thinner necked-down edge sections.
It is an object of the present invention to provide a strip grinding process for manufacturing cutting blades where a plurality of blade stock material strips are fabricated from a single larger sheet (or equivalent) wherein the sheet is necked down along a plurality of spaced apart locations at where cutting edges of the corresponding strips will be sharpened thereon, to a narrower thickness, and then at a later time grinding or sharpening cutting edges on the thinner necked-down edge sections.
It is an object of the present invention to provide a strip grinding process for manufacturing cutting blades where a plurality of blade stock material strips are fabricated from a single larger sheet (or equivalent) wherein the sheet is necked down, by rolling or swaging or stamping, along a plurality of spaced apart locations at where cutting edges of the corresponding strips will be sharpened thereon, to a narrower thickness, then separating the sheet into blade stock material strips, and at a later time grinding or sharpening cutting edges on the thinner necked-down edge sections.
It is still further an object of the present invention to provide a blade stamping process for strip grinding blade manufacture wherein a plurality of blade stock material strips are stamped simultaneously in the same stamping operation wherein the strips each have at least one necked down edge section of a cross-sectional thickness less than the cross-sectional thickness of at least another different section of the corresponding strip, and where at a later time cutting edges are formed or ground on the thinner necked-down edge sections.
It is still further an object of the present invention to provide a process for manufacturing a cutting blade wherein blade forms or blade shapes are stamped into blade stock material and then the blade forms are necked down along an edge thereof that a cutting edge will be sharpened on, to a narrower thickness, and then at a later time grinding or sharpening a cutting edge on the thinner necked-down edge section.
It is yet still further an object of the present invention to provide a process for manufacturing a cutting blade wherein blade forms or blade shapes are stamped into blade stock material and then the blade forms are necked down by rolling or swaging along an edge thereof that a cutting edge will be sharpened on, when the blade stock material is in a non-hardened condition, to a narrower thickness, and then at a later time grinding or sharpening a cutting edge on the thinner necked-down edge section.
It is still further an object of the present invention to provide a process for manufacturing a cutting blade wherein blade forms or blade shapes are stamped into blade stock material and then the blade forms are necked down by rolling or swaging, along the edges thereof that cutting edges will be sharpened on, when the blade stock material is in a non-hardened condition, to a narrower thickness, and then at a later time grinding or sharpening cutting edges on the thinner necked-down edge sections.
It is still further an object of the present invention to provide a process for manufacturing a cutting blade wherein blade stock material is necked down by stamping with a blade stamping die along the edge of the blade stock material a cutting edge will be sharpened on when the blade stock material is in a non-hardened condition, to a narrower thickness, and then at a later time grinding or sharpening a cutting edge on the thinner necked-down edge section.
It is yet still further an object of the present invention to provide a strip grinding process for manufacturing a cutting blade wherein blade stock material is necked down by stamping with a blade stamping die along the edge of the blade stock material a cutting edge will be sharpened on when the blade stock material is in a non-hardened condition, to a narrower thickness, and then at a later time grinding or sharpening a cutting edge on the thinner necked-down edge section.
It is yet still further an object of the present invention to provide a process for manufacturing a cutting blade wherein blade stock material is necked down by rolling at least a section of the edge of blade stock material a cutting edge will be sharpened on when the blade stock material is in a non-hardened condition, to a narrower thickness, and then at a later time grinding or sharpening a cutting edge on the thinner necked-down edge section.
It is even yet still further an object of the present invention to provide a process for manufacturing a cutting blade wherein blade stock material is necked down, by grinding along the side faces adjacent the edge of the blade stock material a cutting edge will be sharpened on, to a narrower thickness, and then at a later time grinding or sharpening a cutting edge on the thinner necked-down side face section or edge section.
The foregoing objects and advantages and other objects and advantages of the present invention are accomplished as according to some of the preferred embodiments of this invention with a mechanical broadhead blade made from 440C stainless steel having a thickness of 0.030xe2x80x3 (inches) with a cutting edge that was ground on a necked down approximately 0.020xe2x80x3 (inch) thick edge portion thereof during a strip grinding process. The blade has a pair of opposing side faces and an inside corner and a step disposed between each side face and the cutting edge. The cutting edge of the blade comprises a pair of opposing primary grind bevels, and a pair of opposing hone bevels. The cutting edge was stropped with leather wheels (or equivalent) to remove microscopic burrs from hone bevel grinding. The angle between the opposing primary grind bevels is approximately 20 degrees and the angle between the opposing hone bevels is approximately 24 degrees. The bevels and steps may be flat or convex or concave or any combination thereof, as viewed in a cross-section of the cutting edge. This provides a 0.030xe2x80x3 thick mechanical broadhead blade, which is of a thickness preferred for blade-opening arrowhead expandable blades due to structural and strength issues, having a much sharper cutting edge (narrower angle between cutting edge bevels) than what standard 0.030xe2x80x3 thick blades in the industry normally have; which for example could be generally approximately 30 degrees between primary grind bevels, and approximately 40 degrees between hone bevels.
The 0.030xe2x80x3 thick 440C stainless steel mechanical broadhead blade as described above, was fabricated from a 0.030xe2x80x3 thick, 440C stainless steel strip (blade stock materialxe2x80x94material cutting blades will be fabricated from) that had an edge section thereof necked down to approximately 0.020xe2x80x3 when the strip was still in a soft condition (not heat treated/hardened yet). The strip was then hardened and the cutting edge was ground on the necked down 0.020xe2x80x3 thinner edge section. The necking down process of the strip edge section could be accomplished before, after or during stamping/cutting the blade shapes or blade forms (precursor blade articles) into the strip during the blade die stamping process. Such method of obtaining an improved sharper blade is manufacturally feasible and cost effective, and would not require excessive grinding time to give the thicker 0.030xe2x80x3 blade the normal cutting edge angles of a thinner 0.020xe2x80x3 blade, while allowing it to retain the normal structural strength, rigidity and integrity of a 0.030xe2x80x3 thick blade.
Another preferred embodiment of this invention comprises a replaceable fixed-blade broadhead blade made from 440C stainless steel having a thickness of 0.027xe2x80x3 with a stropped cutting edge that was ground on an approximately 0.020xe2x80x3 thick edge portion thereof during a strip grinding process. The 0.027xe2x80x3 fixed-blade also has a pair of opposing side faces with an inside corner disposed between each side face and the cutting edge, a pair of opposing primary grind bevels, a pair of opposing hone bevels and an approximately 20 degree angle between the opposing primary grind bevels as well as an approximately 24 degree angle between the opposing hone bevels. This provides a fixed-blade broadhead blade with a 0.027xe2x80x3 thickness that is substantially stronger than 0.020xe2x80x3 thick fixed-blade broadhead blades, but that has the much sharper cutting edge (narrower angle between cutting edge bevels) than what standard 0.027xe2x80x3 thick blades in the archery industry normally have.
The angles between the opposing pairs of like bevels could be different than those set forth above in various different embodiments of this invention, but generally the bevel angles ground/formed on thinner blade stock material sections will be less than the bevel angles ground/formed on thicker blade stock material sections.
Other preferred embodiments as according to this invention include blades and blade stock material having various different thicknesses, such as in the range of 0.002xe2x80x3 to 0.009xe2x80x3 for shaving razor blades for example, and up to one inch or more, but not limited to.
Other preferred embodiments as according to this invention have blades with cutting edges that are not monolinear, such as that which are at least in part serrated, substantially totally serrated, toothed, round, wavy, scalloped, internally or concavely curved/hooked, exteriorly or convexly curved, having a plurality of linear segments that are not collinear with one another, or any plausible combination thereof.
Yet other preferred cutting blade embodiments as according to this invention have cutting edges with only one grind bevel on either side of the cutting edge thereof, whereas other cutting blade embodiments do not.
Yet other preferred cutting blade embodiments as according to this invention have cutting edges with a grind bevel, or grind bevels on one side of the cutting edge and no grind bevels (or equivalents) on the other side of the cutting edge.
Yet other preferred cutting blade embodiments as according to this invention have cutting edges with an inside corner on both sides of the cutting edge, whereas other cutting blade embodiments have an inside corner on only one side of the cutting edge.
Yet other preferred cutting blade embodiments as according to this invention have the blade forms or blade shapes laser cut, water-jet cut, or otherwise cut from a sheet (or equivalent) of blade stock material so as to not be stamped nor fabricated in a strip grinding process.
Yet other preferred cutting blade embodiments as according to this invention have at least one cutting edge formed thereon during a strip grinding process and at least one other cutting edge formed thereon by a non-strip grinding process, such as by a multi-axis CNC grinder.
The cutting blades as according to the desired results and scope of this invention have sharper cutting edges than prior art cutting blades.
The cutting blades as according to the desired results and scope of this invention have sharper cutting edges and are more rigid and structurally strong than prior art cutting blades with similar sharpnesses of cutting edges, or angles between opposing bevels.
The cutting blades as according to the desired results and scope of this invention enable thicker cutting blades to be produced more economically.
The cutting blades as according to the desired results and scope of this invention enable thicker cutting blades having acuter cutting edges to be produced more economically.
The arrowhead cutting blades as according to the desired results and scope of this invention are more lethal than prior art conventional arrowhead cutting blades in that they provide a sharper cutting edge, so as to better cut the game animals and therefore maximize penetration and lethality.
As has been shown in the above discussion, the cutting blades of the arrowheads and the cutting blades of the other cutting devices as according to this invention overcome deficiencies inherent in prior art cutting blades.
With the above objects and advantages in view, other objects and advantages of the invention will more readily appear as the nature of the invention is better understood, the invention is comprised in the novel construction, combination and assembly of parts hereinafter more fully described, illustrated, and claimed.